Combined heat exchanger

ABSTRACT

A combined heat exchanger includes a first heat exchanger, a second heat exchanger accommodated in a first tank of the first heat exchanger, and a third heat exchange disposed above or beneath the first heat exchanger. First refrigerant flowing in the first tank exchanges heat with second refrigerant flowing in the second heat exchanger, and the second refrigerant that has exchanged heat flows into a third tank of the third heat exchanger. The second heat exchanger includes a refrigerant flow-in port and a refrigerant flow-out port. The refrigerant flow-in/flow-out ports are disposed at positions opposed to each other on the first tank. The refrigerant flow-out port is connected with the third tank. According to the combined heat exchanger, the refrigerant flow-in/flow-out ports aren&#39;t protruded laterally outward from the second heat exchanger, and thereby layout flexibility of the refrigerant flow-in/flow-out ports can be improved.

TECHNICAL FIELD

The present invention relates to a combined heat exchanger (to be) installed on a vehicle.

BACKGROUND ART

Various proposes were made for a combined heat exchanger installed on a vehicle (e.g. see Patent Documents 1 and 2 listed below). A combined heat exchanger disclosed in the Patent Document 1 includes a first heat exchanger that cools coolant for electrical devices and a second heat exchanger that condenses refrigerant for air-conditioning. In the first heat exchanger, the coolant in cooled by outside air. The second heat exchanger is disposed in a side tank of the first heat exchanger, and the refrigerant is cooled (condensed) by the coolant flowing in the first heat exchanger.

The heat exchanger disclosed in the Patent Document 2 includes a first heat exchanger (radiator) that cools coolant for an internal combustion engine, and a second heat exchanger (an oil cooler) that cools oil. In the first exchanger, the coolant is cooled by outside air. The second heat exchanger is disposed in a side tank of the first heat exchanger, and the oil is cooled by the coolant flowing in the first heat exchanger.

A combined heat exchanger like these will be explained with reference to FIG. 14 to FIG. 16. The combined heat exchanger disclosed in FIG. 14 to FIG. 16 has a basic configuration equivalent to a basic configuration of the combined heat exchanger disclosed in the Patent Document 1. The combined heat exchanger 100 includes a main radiator (not shown), a sub radiator (first heat exchanger) 110, a water-cooled condenser (second heat exchanger) 120, and an air-cooled condenser 130. The main radiator cools coolant for an internal combustion engine (engine coolant) by outside air. The sub radiator (first heat exchanger) 110 cools coolant for a water-cooled Charge Air Cooler (CAC coolant) by an outside air. The water-cooled condenser (second heat exchanger) 120 exchanges heat between the CAC coolant flowing out from the sub radiator 110 and the refrigerant for air conditioning. The air-cooled condenser 130 cools the refrigerant for air conditioning flowing out from the water-cooled condenser 120 by outside air.

The sub radiator 110 is located above the air-cooled condenser 130. The sub radiator 110 and the air-cooled condenser 130 are disposed along a plane perpendicular to outside-air flow. As shown in FIG. 16, the water-cooled condenser 120 is disposed in a flow-out tank 111 of the sub radiator 110. The water-cooled condenser 120 has a refrigerant flow-in port 121 through which the refrigerant inflows, and a refrigerant flow-out port 122 through which the refrigerant flows out.

The refrigerant flow-in port 121 and the refrigerant flow-out port 122 are protruded from holes 111A and 111B formed on the flow-out tank 111, respectively, and connected with a flow-in pipe 121A and an intermediate pipe 122A by fasteners (such as a nut N, a washer W and a packing P), respectively. The flow-in pipe 121A and the intermediate pipe 122A are protruded laterally outward from the flow-out tank 111 of the sub radiator 110.

PRIOR ART DOCUMENT Patent Documents

Patent Document 1: Japanese Patent Application Publication No. 2005-343221 (Figs. 3, 4 and 6)

Patent Document 2: Japanese Patent Application Publication No. 2000-180089

SUMMARY OF INVENTION

As explained above, the refrigerant flow-in port 121 and the refrigerant flow-out port 122 are protruded laterally outward from the flow-out tank 111 of the sub radiator 110. Therefore, layout flexibility of the refrigerant flow-in port 121, the refrigerant flow-out port 122, the flow-in pipe 121A and the intermediate pipe 122A is spoiled.

An object of the present invention is to provide a combined heat exchanger that can improve layout flexibility of its refrigerant flow-in port and its refrigerant flow-out port while the refrigerant flow-in port and the refrigerant flow-out port are prevented from being protruded laterally outward.

An aspect of the present invention provides a combined heat exchanger comprising: a first heat exchanger; a second heat exchanger that is accommodated in a first tank of the first heat exchanger; and a third heat exchanger that is disposed above or beneath the first heat exchanger, wherein first refrigerant flowing in the first tank exchanges heat with second refrigerant flowing in the second heat exchanger, and the second refrigerant that has exchanged heat flows into a third tank of the third heat exchanger, the second heat exchanger includes a refrigerant flow-in port into which the second refrigerant flows and a refrigerant flow-out port from which the second refrigerant flows out, the refrigerant flow-in port and the refrigerant flow-out port are disposed at positions opposed to each other on the first tank, and the refrigerant flow-out port is connected with the third tank.

According to the aspect, the refrigerant flow-in port and the refrigerant flow-out pert are disposed at positions opposed to each other on the first tank, and the refrigerant flow-out port is connected with the third tank. Therefore, the refrigerant flow-in port and the refrigerant flow-out port are not protruded laterally outward from the second heat exchanger, and thereby layout flexibility of the refrigerant flow-in port and the refrigerant flow-in port can be improved.

In addition, it is preferable that the first tank is protruded outward from the third tank, and the refrigerant flow-out port is arranged in a space formed on an outside of the third tank, and is connected with the third tank via an intermediate pipe communicating with the third tank.

In addition, it is preferable that it further comprises a refrigerant accumulation tank that accumulates the second refrigerant flowing in the third heat exchanger, wherein the refrigerant accumulation tank is disposed on an opposite side to the third tank in the third heat exchanger.

In addition, it is preferable that the third tank includes a flow-in position at which she second refrigerant inflows, and a flow-out position at which the second refrigerant outflows, and the flow-in position and the flow-out position are distanced away from each other.

In addition, it is preferable that the third tank includes a connector that is connected with the refrigerant flow-out port.

Or, it is preferable that the refrigerant flow-in port is directly connected with the third tank.

In addition, it is preferable that the first heat exchanger is a sub radiator, the second heat exchanger is a water-cooled condenser, and the third heat exchanger is a air-cooled condenser.

In addition, it is preferable that an insertion hole through which the second heat exchanger is inserted into the first tank, and an opening opposed to the insertion hole are formed on the first tank, the second heat exchanger includes a plurality of tubes, a pair of tanks that are connected with both ends of the tubes, the refrigerant flow-in port is attached to one of the tanks, the refrigerant flow-out port is attached to another of the tanks, one side of the second heat exchanger where the one of the tanks and the refrigerant flow-in port are provided is fixed with the insertion hole, and the refrigerant flow-in port is exposed outside, and another side of the second heat exchanger where the other of the tanks and the refrigerant flow-out port are provided is fixed with the opening.

Further, it is preferable that each of the refrigerant flow-out port and the opening is formed to have a hollow cylindrical shape, and the other side of the second heat exchanger is fixed with the opening in a state where the refrigerant flow-out port passes through the opening.

Furthermore, it is preferable that a sealing member is interposed between the refrigerant flow-out port and the opening.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view at a combined heat exchanger according to a first embodiment.

FIG. 2 is a front view of the combined heat exchanger.

FIG. 3 is a configuration diagram of a heat exchanging system that includes the combined heat exchanger.

FIG. 4 is a front view of a flow-out tank of a sub radiator in the combined heat exchanger.

FIG. 5 is an exploded perspective view of the flow-out tank and a water-cooled condenser in the combined heat exchanger.

FIG. 6 is an enlarged perspective view of the flow-out tank and the water-cooled condenser.

FIG. 7 is an enlarged cross-sectional view of the flow-out tank and the water-cooled condenser.

FIG. 8 is a perspective view of a first side tank of the flow-out tank and an air-cooled condenser.

FIG. 9 is an exploded perspective view of the water-cooled condenser.

FIG. 10 is a front view of a flow-out tank of a sub radiator and a first side tank of an air-cooled condenser in a first modified example.

FIG. 11 is a front view of a flow-out tank of a sub radiator and a first side tank of an air-cooled condenser in a second modified example.

FIG. 12 is an exploded perspective view of a flow-out tank of a sub radiator and a water-cooled condenser in a combined heat exchanger according to a second embodiment.

FIG. 13( a) is an enlarged cross-sectional view of the flow-out tank and the water-cooled condenser, and FIG. 13( b) is a further enlarged cross-sectional view of FIG. 13( a).

FIG. 14 is a front view of an example of a combined heat exchanger that includes a basic configuration equivalent to a basic configuration of a combined heat exchanger disclosed in the Patent Document 1.

FIG. 15 is a perspective view of a blow-out tank of a sub radiator and a first side tank of an air-cooled condenser in the combined heat exchanger.

FIG. 16 is an exploded perspective view of the flow-out tank and a water-cooled condenser in the combined heat exchanger.

FIG. 17 is an exploded perspective view of a combined heat exchanger disclosed in the Patent Document 2.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of a combined heat exchanger will be explained with reference to the drawings. Note that identical or equivalent components to each other are labeled with identical reference numbers, respectively. Also, in the drawings, their dimensions, proportions or the like may be different from actual ones. Therefore, specific dimensions or the like should be understood in consideration of following descriptions. In addition, dimensions, proportions or the like may be shown differently among the drawings.

First Embodiment

A combined heat exchanger 1 according to a first embodiment will be described with reference to FIG. 1 to FIG. 9.

(Configuration of Combined Heat Exchanger)

As shown In FIG. 1 to FIG. 3, the combined heat exchanger 1 includes a main radiator 10, a sub radiator (first heat exchanger) 20, a water-cooled condenser (second heat exchanger) 30 accommodated in a flow-out tank (fist tank) 23 of the sub radiator 20, and a air-cooled condenser (third heat exchanger) 40 disposed beneath the sub radiator 20. In the combined heat exchanger 1, heat is exchanged between coolant for the water-cooled charge air cooler 3 (CAC coolant; first refrigerant) flowing in the flow-out tank 23 and refrigerant for air-conditioning (A/C refrigerant: second refrigerant) flowing in the water-cooled condenser 30. The A/C refrigerant flows into a first side tank (third tank) 42 of the air-cooled condenser 40.

The main radiator 10 cools coolant for an internal combustion engine (hereinafter, simply referred as the engine) 2 (engine coolant). The main radiator 10 is disposed in front of a motor fan (on an upstream side of cooling-air flow). The main radiator 10 has plural tubes, and fins disposed between the tubes. The engine coolant flows in the tubes, and exchanges heat with cooling-air passing through the main radiator 10. The engine coolant is circulated by a pump 5.

The sub radiator 20 cools the CAC coolant. The sub radiator 20 is disposed at an upper position in front of the main radiator 10. The sub radiator 20 includes plural tubes 21 (not shown one by one), fins disposed between the tubes 21, and a pair of tanks (a flow-in tank 22 and the flow-out tank 23). The flow-in tank 22 and the flow-out tank 23 are connected with both ends of the plural tubes 21, respectively. The CAC coolant flows in the tubes 21, and exchanges heat with cooling-air passing through the sub radiator 20. The CAC coolant is circulated by a pump 6.

A flow-in port 22in through which the CAC coolant inflows is formed on the flow-in tank 22, and a flow-out port 23out through which the CAC coolant outflows is formed on the flow-out tank 23. The flow-out tank 23 is protruded outward from the first side tank 42 of the air-cooled condenser 40 (see FIG. 1 and FIG. 2). An accommodation chamber 23A that accommodates the water-cooled condenser 30 is provided in the flow-out tank 23 (see FIG. 4 to FIG. 7).

An upper insertion hole (an insertion hole) 23A1 into which the water-cooled condenser 30 is inserted is formed at an upper portion of the accommodation chamber 23A. A sealing seat 23B on which an O-ring 34 of the water-cooled condenser 30 is disposed is formed at the upper insertion hole 23A1 (see FIG. 5 to FIG. 7. In addition, an attachment flange 23T to which a cap 36 of the water-cooled condenser 30 is attached is formed along an outer circumference of the upper insertion hole 23A1. A pair of guide rails 23C that guide rotations of the cap 36 is formed on the attachment flange 23T.

A hollow cylindrical lower opening (an opening) 23A2 is formed at a lower portion of the accommodation chamber 23A so as to be opposed to the upper insertion hole 23A1. A refrigerant flow-out port 38 of the water-cooled condenser 30 is inserted into the lower opening 23A2.

In the water-cooled condenser 30, the A/C refrigerant and the CAC coolant flowing out from the sub radiator 20 exchange heat with each other. The water-cooled condenser 30 is accommodated in the flow-out tank 23 of the sub radiator 20 (see FIG. 4 to FIG. 7). The water-cooled condenser 30 and the air-cooled condenser 40 are connected serially with each other on an air-conditioning refrigeration cycle.

The air-cooled condenser 40 cools the A/C refrigerant flowed out from the water-cooled condenser 30. As shown in FIG. 3, the air-cooled condenser 40 is disposed in front of the main radiator 10 (on an upstream side of cooling-air flow), and disposed beneath the sub radiator 20 as described above. The sub radiator 20 and the air-cooled condenser 40 are disposed along a plane perpendicular to outside-air flow. The air-cooled condenser 40 includes plural tubes 41 (not shown one by one), fins disposed between the tubes, and a pair of tanks (the first side tank 42 and a second side tank 43). The first side tank 42 and the second side tank 43 are connected with both ends of the plural tubes 41, respectively. The A/C refrigerant flows in the tubes 41, and exchanges heat with cooling-air passing through the air-cooled condenser 40.

As described above, the flow-out tank 23 of the sub radiator 20 is protruded outward from the first side tank 42 (see FIG. 1 and FIG. 2). Namely, a space S (see FIG. 2) at which the above-described lower openign23A2 can be disposed is formed outside the first side tank 42 and beneath the sub radiator 20. (In other words, the flow-out tank 23 of the sub radiator 20 is protruded laterally outward from the first side tank 42, and the space S is formed outside the first side tank 42 and beneath the sub radiator 20.)

The inside of the first side tank 42 is divided into a flow-in section 42A into which the A/C refrigerant that not yet exchange heat flows from the water-cooled condenser 30, and a flow-out section 42B into which the A/C refrigerant that has already exchanged heat flows. The flow-in section 42A is provided at an upper portion of the first side tank 42, and the flow-out section 42B is provided at a lower portion of the first side tank 42. One end of an intermediate pipe 50 is connected with the refrigerant flow-out port 38 of the water-cooled condenser 30, and another end is connected with the flow-in section 42A. The other end of the intermediate pipe 50 is brazed to the first side tank 42 (at a flow-in position 42A1). The A/C refrigerant that not yet exchange heat flows into the first side tank 42 at the connection portion of the flow-in section 42A and the intermediate pipe 50, i.e. at the flow-in position 42A1. In addition, the A/C refrigerant that has already exchanged heat flows out from the first side tank 42 at a flow-out position 42B1 of the flow-out section 42B. The flow-in position 42A1 and the flow-out position 42B1 are distanced away from each other.

The inside of the second side tank 43 is also divided into a flow-in section 43A and a flow-out section 43B. A liquid tank (refrigerant accumulation tank) 60 is provided beside on a lateral side of the second side tank 43 (see FIG. 1 and FIG. 2), and the flow-in section 43A and the flow-out section 43B are communicated with each other via the liquid tank 60. Namely, the A/C refrigerant flows through the flow-in section 42A, the tubes 41 (a condensing section) between the flow-in sections 42A and 43A, the flow-in section 43A, the liquid tank 60, the flow-out section 43B, the tubes 41 (a sub-cooling section) between the flow-out sections 43B and 42B, and the flow-out section 42B in this order. The liquid tank (refrigerant accumulation tank) 60 is also called as a gas-liquid separator or a modulator.

(Configuration of Water-Cooled Condenser)

The water-cooled condenser 30 will be described in detail. As shown in FIG. 5 and FIG. 9, the water-cooled condenser 30 includes plural tubes 31, a pair of tanks 32 and 33, the large O-ring 34, a disc-shaped sealing plate 30, the ring-shaped cap 36, a refrigerant flow-in port 37, the refrigerant flow-out port 38, and two small O-ring (sealing members) 39.

The A/C refrigerant flows in the tubes 31, and exchanges heat with the CAC coolant flowing in the flow-out tank 23. Each of the tubes 31 is disposed between the pair of the tanks 32 and 33. Each of the tubes 31 is formed by extrusion molding, for example. The tanks 32 and 33 are connected with both ends of the plural tubes 31, respectively. The tank 32 (33) is comprised of an inner plate 32A (33A) on which holes 32A1 (33A1) to which ends of the tubes 31 are connected are formed, and an outer plate 32B (33B) that is attached to the inner plate 32A (33A). A refrigerant flow port 32B1 (33B1) through which the A/C refrigerant passes is formed on the outer plate 32B (33B).

The O-ring 34 is disposed on the sealing seat 23B formed on an upper surface of the flow-out tank 23. The sealing plate 35 is disposed on the O-ring 34. The sealing plate 35 contacts with the O-ring 34 and an upper edge of the upper insertion hole 23A1 to prevent the CAC refrigerant in the flow-out tank 23 from leaking out. A refrigerant flow hole 35A is formed at the center of the sealing plate 35. A circular bead 358 that is bulged toward the cup 36 is formed on an outer of the refrigerant flow hole 35A. The cap 36 is attached to the upper portion of the flow-out tank 23 so as to press the sealing plate 35 onto the O-ring 34.

The cap 36 has a pair of tabs 36A that are rotated along the guide rails 23C of the flow-out tank 23. When the cap has bean attached to the flow-out tank 23, the water-cooled condenser 30 is fixed in the inside of the flow-out tank 23. As show in FIG. 7, the refrigerant flow-in port 37 is fixed with the refrigerant flow port 32B1 of the upper tank 32 while the sealing plate 35 is interposed therebetween. The refrigerant flow-out port 38 is fixed with the refrigerant flow port 33B1 of the lower tank 33.

The refrigerant flow-in port 37 functions as a flow-in port of the A/C refrigerant to the water-cooled condenser 30. One side (upper side) of the water-cooled condenser 30 is fixed at a position of the upper insertion hole 23A1, and the refrigerant flow-in port 37 is protruded upward from the cap 36. On the other hand, the refrigerant flow-out port 38 functions as a flow-out port of the A/C refrigerant from the water-cooled condenser 30. The refrigerant flow-out port 38 is formed to have a hollow cylindrical shape, and inserted into the lower opening 23A2 of the flow-out tank 23. Then another side (lower side) of the water-cooled condenser 30 is fixed at different positions of the lower opening 23A2, and the refrigerant flow-out port 38 is protruded downward from the lower opening 23A2. As described above, the refrigerant flow-out port 38 is connected with the first side tank 42 via the intermediate pipe 50.

Grooves 38A to which the O-rings 39 are attached are formed on an outer circumference of the refrigerant flow-out port 38. A minute gap between the refrigerant flow-out port 38 and the lower opening 23A2 is sealed by the O-rings 39. The refrigerant flow-out port 38 is supported by the lower opening 23A2, and arranged in the space S (see FIG. 2).

The water-cooled condenser 30 inserted into the flow-out tank 23 from the upper insertion hole 23A1 is fixed with the flow-out tank 23 at two positions, the upper insertion hole 23A1 and the lower opening 23A2.

Flows of the CAC coolant (first refrigerant), the A/C refrigerant (second refrigerant) and the engine coolant in the combined heat exchanger 1 will be described with reference to FIG. 3.

Intake air to be supplied to the engine 2 is compressed at a turbocharger 7, and thereby gets high temperature. Therefore, this compressed high-temperature intake air is cooled by the water-cooled charge air cooler 3. As a result, intake air density is improved, and thereby combustion efficiency of the engine 2 is improved. At the water-cooled charge air cooler 3, heat is exchanged between the intake air and the CAC coolant to cool the intake air. The CAC coolant flowing through the water-cooled charge air cooler 3 is cooled by the A/C refrigerant flowing through the water-cooled condenser 30 while flowing in the flow-out tank 23 of the sub radiator 20, and then further cooled at the water-cooled condenser 30. The CAC coolant flowed out from the water-cooled condenser 30 is send to the water-cooled charge air cooler 3 by the pump 5.

On the other hand, the high-temperature and high-pressure A/C refrigerant compressed by a compressor 8 of the air-conditioning refrigeration cycle flows into the water-cooled condenser 30, and then flows into the air-cooled condenser 40. The A/C refrigerant flowing into the air-cooled condenser 40 flows through the condensing section on the upper side of the air-cooled condenser 40, liquid tank 60 and the sub-cooling section on the lower side, and then flows out from the flow-out section 42B.

(Advantages)

In the combined heat exchanger 1 according to the present embodiment, the refrigerant flow-in port 37 and the refrigerant flow-out port 38 are disposed at positions opposite to each other on the flow-out tank 23 of the sub radiator 20, and the refrigerant flow-out port 38 is connected to the first side tank 42. Therefore, the refrigerant flow-in port 37 and the refrigerant flow-out port 38 are not protruded laterally outward from the sub radiator 20, and thereby layout flexibility of the refrigerant flow-in port 37 and the refrigerant flow-out pert 38 (especially, a flow-in pipe connected with the refrigerant flow-in port 37 and the intermediate pipe 50 connected with the refrigerant flow-out port 38) can be improved. Further, compared with the combined heat exchanger above-described with reference to FIG. 24 to FIG. 16, the intermediate pipe 50 connected with the refrigerant flow-out port 38 can be shortened, and thereby the intermediate pipe 50 can be simplified.

Note that the combined heat exchanger 1 is needed to be arranged in a limited installation zone Y (see FIG. 2) in an engine compartment. Since the refrigerant flow-in port 37 and the refrigerant flow-out port 38 are not protruded laterally outward from the sub radiator 20 as described above, a heat exchanging area X (see FIG. 2: area of the tubes 21) can be expanded by locating the flow-out port 23out protruded from the flow-out tank 23 on an outside of the installation zone Y. Note that the flow-out port 23out is not necessarily provided on a side wall of the flow-out tank 23, but may be provided on an upper face or a bottom face of the flow-out tank 23. In this case, the heat exchanging area X can be expanded certainly.

Since the water-cooled condenser 30 is provided within the flow-out tank 23, the flow-out tank 23 is bigger than the first side tank 42 of the air-cooled condenser 40. Therefore, the flow-out tank 23 is protruded outward from the first side tank 42. As a result, the refrigerant flow-out port 38 and the intermediate pipe 50 can be arranged in the space S beneath the flow-out tank 23, so that the space S can be utilized effectively.

The liquid tank 60 is attached to the second side tank 43 on an opposite side to the first side tank 42 into which the A/C refrigerant flows. Therefore, a space on an opposite side to the flow-in tank 23 where the water-cooled condenser 30 is provided can be utilized effectively to utilize spaces in the engine compartment, and thereby layout flexibility of various components can be improved.

The flow-in position 42A1 and the flow-out position 42B1 that are provided on the first side tank 42 are distanced away from each other. Therefore, the A/C refrigerant that flows through the sub-cooling section of the air-cooled condenser 40 and then outflows from the flow-out position 42B1 (refrigerant after being cooled) is hardly affected by heat of the A/C refrigerant that inflows from the flow-in position 42A1 and then flows through the condensing section of the air-cooled condenser 40 (refrigerant before being cooled), and thereby heat exchanging efficiency of the A/C refrigerant at the air-cooled condenser 40 can be improved.

By the water-cooled condenser 30 (second heat exchanger), the A/C refrigerant to be flowed into the air-cooled condenser 40 can be preliminarily cooled, and thereby the air-cooled condenser 40 can be down-sized.

The intermediate pipe 50 is brazed to the first side tank 42. Therefore, an attaching work or the intermediate pipe 50 to the first side tank 42 is not needed, so that assembling workability of the combined heat exchanger 1 can be improved.

The upper tank 32 and the one side (upper side) of the water-cooled condenser 30 where the refrigerant flow-in port 37 is provided are fixed with the upper insertion hole 23A1, and the lower tank 33 and the other side (lower side) of the water-cooled condenser 30 where the refrigerant flow-out port 38 is provided are fixed with the lower opening 23A2. Namely, the water-cooled condenser 30 is fixed at two position, the upper insertion hole 23A1 and the lower opening 23A2 that are opposed to each other. Therefore, vibrations of the water-cooled condenser 30 in the flow-out tank 23 can be prevented surely.

The O-rings 39 are interposed between the outer circumference of the lower opening 23A2 and an inner circumference of the lower opening 23A2 in a state where the refrigerant flow-out port 38 passes through the lower opening 23A2. Therefore, the CAC refrigerant flowing through the flow-out tank 23 can be prevented from leaking out. Further, even if the water-cooled condenser 30 is expanded or shrined due to the thermal-expansion, it is slidable against compressing force of the refrigerant flow-out port 38 and thereby the expansion or the shrinkage of the water-cooled condenser 30 can be addressed.

Since the tubes 31 are formed by extrusion molding, the A/C refrigerant flowing through the tubes 31 can be prevented from leaking out surely, and the tubes 31 can be made easily.

The water-cooled condenser 30 can be fixed with the flow-out tank 23 only by rotating the cap 36 while guiding it along the guide rails 23C. In addition, the water-cooled condenser 30 can be removed from the flow-out tank 23 only by detaching the cap 36. Therefore, maintenance of the water-cooled condenser 30 is easy.

Further, by the combined heat exchanger 1 according to the present embodiment, an advantage that troubles caused by vibrations of the water-cooled condenser 30 in the flow-out tank 23 can be prevented can be also brought. This advantage will be described in detail with reference to FIG. 17.

FIG. 17 shows a combined heat exchanger (a water-cooled condenser 200 accommodated in a flow-out tank 203 of a sub radiator 201) disclosed in the above-mentioned Patent Document 2. A/C refrigerant flowing through the water-cooled condenser 200 exchanges heat with CAC coolant flowing through the sub radiator 201. An insertion hole 205 through which the water-cooled condenser 200 is inserted is formed on an upper face of the flow-out tank 203.

The water-cooled condenser 200 includes a screw cap (an upper tank) 210 attached to the insertion hole 205, a pair of a flow-in pipe 220A and a flow-out pipe 220B through which the A/C refrigerant inflows and outflows respectively, tubes 230 in which the A/C refrigerant flows, baffle plates 240 supporting the tubes 230, and a lower tank 250 that changes flowing direction of the A/C refrigerant. The water-cooled condenser 200 is fixed with the flow-out tank 203 by the screw cap 210.

Since the water-cooled condenser 200 is fixed with a flow-out side of the flow-out tank 203 only by the screw cap 210, its end portion (portion on a side of the lower tank 250) vibrates due to vibrations (e.g. vibrations caused by accelerations of a vehicle). As a result, there may be a concern that the insertion hole 205 or the screw cap 210 may be damaged due to vibratory loads.

On the other hand, in the combined heat exchanger 1 according to the present embodiment, the water-cooled condenser 30 is fixed with the flow-out tank 23 at the upper insertion hole 23A1 and the lower opening 23A2 of the flow-out tank 23. Therefore, vibrations of the flow-out tank 23 in the flow-out tank 23 can be prevented as described above, and thereby troubles caused by the vibrations can be prevented.

MODIFIED EXAMPLES OF FIRST EMBODIMENT

Next, modified examples of the first side tank 42 will be described with reference to the drawings. Note that identical or equivalent configurations to the configurations in the above embodiment will be labeled with identical reference numbers, and thereby their redundant descriptions will be omitted. Hereinafter, different configurations will be described.

Modified Example 1

As shown in FIG. 10, a connector 70 connected with the intermediate pipe 50 is provided on the first side tank 42. An internal flow passage 71 is formed within the connector 70. One end of the flow passage 71 is opened upward, and another end is opened toward the flow-in section 42A of the first side tank 42. The connector 70 may be brazed to the first side tank 42, or may be fixed with the first side tank 42 by another method such as swaging.

According to the modified example 1, in addition to the above-described advantages according to the above embodiment, the intermediate pipe 50 can be made straight by providing the connector 70 on the first side tank 42, and thereby the intermediate pipe 50 can be simplified. The intermediate pipe 50 is connected with the connector 70 here, but the refrigerant flow-out port 38 of the water-cooled condenser 30 may be directly connected to the connector 70.

Modified Example 2

As shown in FIG. 11, the refrigerant flow-out port 38 is directly connected to the first side tank 42 without interposing the intermediate pipe 50 in the above embodiment and the connector 70 in the above modified example 1. A sealing member for preventing the A/C refrigerant from leaking out may be provided on a circumference of a hole into which the refrigerant flow-out port 38 is inserted.

According to the modified example 2, in addition to the above-described advantages according to the above embodiment, the intermediate pipe 50 and the connector 70 are made unnecessary by directly connecting the refrigerant flow-out port 38 to the first side tank 42.

Second Embodiment

Next, a combined heat exchanger according to the second embodiment will be described with reference to FIG. 12, FIG. 13( a) and FIG. 13( b). A water-cooled condenser 30 in the combined heat exchanger according to the present embodiment is only different from the water-cooled condenser 30 in the above-described first embodiment. Therefore, only the water-cooled condenser 30 will be described hereinafter. Note that identical or equivalent configurations to the configurations in the above first embodiment will be labeled with identical reference numbers, and thereby their redundant descriptions will be omitted.

(Configuration of Water-Cooled Condenser)

As shown in FIG. 12, FIG. 13( a) and FIG. 13( b), a portion of the upper tank 32 of the water-cooled condenser 30 is exposed above the flow-out tank 23 in the present embodiment. Similarly to the first embodiment, the water-cooled condenser 30 includes the plural tubes 31 (not shown one by one), the pair of the tanks 32 and 33, the O-ring 34, the refrigerant flow-in port 37, and the refrigerant flow-out port 38.

The upper tank 32 is comprised of the inner plate 32A on which holes to which ends of the tubes 31 are connected are formed, and the outer plate 32B that is attached to the inner plate 32A. As shown in FIG. 13( a), a flange 72 extended outward from the accommodation chamber 23A of the flow-out tank 23 is formed on the inner plate 32A. The flange 72 functions similarly to the sealing plate 35 in the first embodiment.

The O-ring 34 is disposed between the flange 72 and the sealing seat 23B of the flow-out tank 23. The flange 72 is fixed with the attachment flange 23T of the flow-out tank 23 by a pair of divided pinching adapters 80. The two divided pinching adapters 30 are fixed with each other by fixture tabs 81 and 32.

No flange 72 is formed on the lower tank 33, and the tank 33 has an almost identical configuration to that in the first embodiment. Therefore, descriptions of the tank 33 are omitted.

(Advantages)

By the present embodiment, all the advantaged described in the first embodiment can be brought. In addition to the advantages, a portion of the tank 32 of the water-cooled condenser 30 is exposed in the present embodiment. Therefore, a volume, in the flow-out tank 23, occupied by the water-cooled condenser 30 can be made reduced, and thereby the flow-out tank 23 can be down-sized.

In addition, it is needless to provide the flange 72 as an additional part because the flange 72 is formed on the inner plate 32A, so that the water-cooled condense r30 can be light-weighted and manufacturing costs of the water-cooled condenser 30 can be reduced.

Note that, although the flange 72 is provided on the inner plate 32A, it may be formed integrally with the tubes 31 or may be formed integrally with the outer plate 32B or the refrigerant flow-in port 37.

The present invention is not limited to the above-described embodiments. Scope of the present invention is determined in the context of the claims. For example, in the above embodiments, the sub radiator 20 and the air-cooled condenser 40 are disposed along a plane perpendicular to outside-air flow. However, the sub radiator 20 and the air-cooled condenser 40 may be arranged backward and forward so as to be slightly set off to each other.

In addition, the sub radiator 20 is disposed above the air-cooled condenser 40 in the above embodiments. However, the air-cooled condenser 40 may be disposed above the sub radiator 20.

In addition, the sub radiator 20 cools the CAC coolant of the water-cooled condenser 30 in the above embodiments. However, the sub radiator 20 may cool refrigerant used for carious electrical devices installed on a vehicle (e.g. coolant for cooling an inverter).

In addition, the water-cooled condenser 30 is provided as the second heat exchanger in the above embodiments. However, the second heat exchanger may be an oil cooler.

In addition, the water-cooled condenser 30 is accommodated in the flow-out tank 23 of the sub radiator 20 in the above embodiments. However, the water-cooled condenser 30 may be accommodated in the flow-in tank 22 of the sub radiator 20. Also in this case, the A/C refrigerant flowing through the water-cooled condenser 30 exchanges heat with the CAC coolant flowing through the sub radiator 20.

In addition, the water-cooled condenser 30 is inserted into the flow-out tank 23 through the upper insertion hole 23A1 in the above embodiments. However, the water-cooled condenser 30 may be inserted into the flow-out tank 23 from beneath by design change.

In addition, the tubes 31 are formed by extrusion molding in the above embodiments. However, the tubes 31 may be formed by a method other than extrusion molding. For example, the tube(s) 31 may be an inner-fin tube, a tube having a refrigerant passage, a pipe member and so on.

In addition, the water-cooled condenser 30 is fixed with the flow-out tank 23 at the upper insertion hole 23A1 and the lower opening 23A2. However, the water-cooled condenser 30 may be fixed with the flow-out tank 23 at two or more positions along its longitudinal direction (other than the upper insertion hole 23A1 and the lower opening 23A2). 

1. A combined heat exchanger comprising: a first heat exchanger; a second heat exchanger that is accommodated in a first tank of the first heat exchanger; and a third heat exchanger that is disposed above or beneath the first heat exchanger, wherein first refrigerant flowing in the first tank exchanges heat with second refrigerant flowing in the second heat exchanger, and the second refrigerant that has exchanged heat flows into a third tank of the third heat exchanger, the second heat exchanger includes a refrigerant flow-in port into which the second refrigerant flows and a refrigerant flow-out port from which the second refrigerant flows out, the refrigerant flow-in port and the refrigerant flow-out port are disposed at positions opposed to each other on the first tank, and the refrigerant flow-out port is connected with the third tank.
 2. The combined heat exchanger according to claim 1, wherein, the first tank is protruded outward from the third tank, and the refrigerant flow-out port is arranged in a space formed on an outside of the third tank, and is connected with the third tank via an intermediate pipe communicating with the third tank.
 3. The combined heat exchanger according to claim 1, further comprising a refrigerant accumulation tank that accumulates the second refrigerant flowing in the third heat exchanger, wherein the refrigerant accumulation tank is disposed on an opposite side to the third tank in the third heat exchanger.
 4. The combined heat exchanger according to claim 1, wherein the third tank includes a flow-in position at which the second refrigerant inflows, and a flow-out position at which the second refrigerant outflows, and the flow-in position and the flow-out position are distanced away from each other.
 5. The combined heat exchanger according in claim 1, wherein the third tank includes a connector that is connected with the refrigerant flow-out port.
 6. The combined heat exchanger according to claim 1, wherein the refrigerant flow-out port is directly connected with the third tank.
 7. The combined heat exchanger according to claim 1, wherein the first heat exchanger is a sub radiator, the second heat exchanger is a water-cooled condenser, and the third heat exchanger is an air-cooled condenser.
 8. The combined heat exchanger according to claim 1, wherein an insertion hole through which the second heat exchanger is inserted into the first tank, and an opening opposed to the insertion hole are formed on the first tank, the second heat exchanger includes a plurality of tubes, a pair of tanks that are connected with both ends of the tubes, the refrigerant flow-in port is attached to one of the tanks, the refrigerant flow-out port is attached to another of the tanks, one side of the second heat exchanger where the one of the tanks and the refrigerant flow-in port are provided is fixed with the insertion hole, and the refrigerant flow-in port is exposed outside, and another side of the second heat exchanger where the other of the tanks and the refrigerant flow-out port are provided is fixed with the opening.
 9. The combined heat exchanger according to claim 8, wherein each of the refrigerant flow-out part and the opening is formed to have a hollow cylindrical shape, and the other side of the second heal exchanger is fixed with the opening in a state where the refrigerant flow-out port passes through the opening.
 10. The combined heat exchanger according to claim 9, wherein a sealing member is interposed between the refrigerant flow-out port and the opening. 